Postgres 14

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CREATE tABLE waste("createdAt" timestamp  , "Quantity" integer )

CREATE TABLE


CREATE tABLE sales_hourly("createdAt" timestamp  , "Quantity" integer)

CREATE TABLE


SELECT t1.week_t1,COALESCE(sum_t1,0) sum_waste,t2.week_t2,  COALESCE(sum_t2,0) sum_slaes
FROM
(
    SELECT date_part('week', w."createdAt") week_t1,
        SUM("Quantity") sum_t1
    FROM waste as w
     WHERE date_trunc('year', w."createdAt"::timestamptz at time zone 'America/Denver') =
           date_trunc('year', current_date - interval '1 year')
    group by 1
) t1
    FULL OUTER JOIN 
(
    SELECT date_part('week', sh."createdAt") week_t2,
        SUM("Quantity") sum_t2
    FROM sales_hourly as sh
     WHERE date_trunc('year', sh."createdAt"::timestamptz at time zone 'America/Denver') =
           date_trunc('year', current_date - interval '1 year')
    group by 1) t2 ON t1.week_t1 = t2.week_t2


week_t1
sum_waste
week_t2
sum_slaes



SELECT 0